New study examines economic benefits of tornado-related building codes

After suffering two violent tornadoes in May 2013, resulting in 27 fatalities and an estimated $3 billion in damages, the city of Moore, Oklahoma adopted enhanced building codes in early 2014, which were implemented to encourage and enforce better wind resistant construction for homes and other structures.

A new study led by researchers at Western University, the Institute for Catastrophic Loss Reduction and Austin College (Sherman, Texas) shows that the Moore building codes successfully deliver a number of possible solutions that will improve the architectural integrity of residential and business buildings in order to prevent further human casualties and should be adopted statewide.

The researchers, including Gregory Kopp from Western Engineering, also recommend the implementation of further inexpensive mitigation measures, estimated to increase building costs by just $1 per square foot, which will potentially enhance public safety and structural sufficiency.

"Annual losses from tornadoes are approaching those from hurricanes," says Kopp, a director of Western's Boundary Layer Wind Tunnel Laboratory and current chair of the American Society of Civil Engineers (ASCE) Environmental Wind Engineering Committee. "Building codes are known to be an effective way to reduce damage and the Moore building code is the first to do so for tornadoes. Our analysis has shown that doing this would be cost effective for the state to reduce tornado damage."

While Canadian building codes are different from American building codes, Kopp believes that recent studies indicate similar steps should be considered in Canada, particularly along the 401 corridor from the Great Lakes region to the upper St. Lawrence Valley.

"Our recent analysis of damaging tornadoes in Canada suggests that inexpensive mitigation measures, such as using hurricanes straps to hold-down the roof, could also reduce or eliminate structural damage to houses in tornadoes like the one that hit Angus, Ontario last June," explains Kopp.

Kopp collaborated with Paul Kovacs from the Institute for Catastrophic Loss Reduction and Kevin M. Simmons from Austin College on the study. The findings were published by Weather, Climate and Society, a journal of the American Meteorological Society, in an article titled "Tornado Damage Mitigation: Benefit/Cost Analysis of enhanced Building Codes in Oklahoma."